Antenna rotator



Feb. 28, 1950 JORDAN 2,498,957

ANTENNA ROTATOR Filed NOV. 19, 1948 2 Sheets-Sheet l ALTERNAT/NG TJ CURRENT 4 12, 70 INVENTOR. sou/ace 6 R/CHARD JORDAN Feb. 28, 1950 R. H. JORDAN 2,498,957

ANTENNA ROTATOR Filed Nov. 19, 1848 2 Sheets-Sheet 2 L INVENTOR.

R/CHARD H JO/QOAN i BY mi 99? W g/g Patented Feb. 28, 1950 ANTENNA ROTATOR Richard H. Jordan, Mansfield, Ohio, assignor to The Alliance Manufacturing Company, a corporation of Ohio Application November 19, 1948, Serial No. 60,873

17 Claims.

The invention relates in general to rotating mechanisms and more particularly to a device for rotating a shaft relative to a housing, such as the shaft of an antenna rotatable relative to a supporting housing.

In the utilization of higher frequency electromagnetic waves, such as are at present being used for frequency modulation and television channels, the problem of quickly and accurately orienting an antenna to better receive a desired signal is becomingmore acute. This invention deals with such problem of quickly and accurately orienting an antenna array. By the use of a rotatable and directional receiving antenna array, the maximum signal strength of a desired signal may be obtained by rotation of this antenna in a horizontal plane. Also, where two signals are interfering, the antenna array may be oriented in a direction to receive a minimum signal strength from the interfering signal to thus achieve a maximum of desired signal to interferenceratio. A great majority of the receiving antenna arrays available at present for frequency modulation and television reception are of the dipole or folded dipole type with or without reflecting dipoles, and are mounted on or are adapted to be mounted on a vertical cylindrical shaft, such as standard electrical thin wall conduit. A specific object of this invention is to provide a weatherproof rotator mechanism which may carry and rotate an antenna array and which may be remotely controlled by a remote control box placed near the radio or television receiver.

An object of the invention is to provide relative rotation movements between two shafts.

A further object of the invention is to provide a device for rotating an antenna such as a radio.

or television antenna.

A further object of the invention is to provide an electrically powered device for rotating an antenna which willbe waterproof, light and strong.

Another object of the invention is to provide a device for rotating an antenna having a shaft wherein the shaft is receivable within a hollow shaft of the rotator and such hollow shaft has spaced bearing and clamping means to clamp to the antenna shaft.

A further object of the invention is to provide an antenna rotating mechanism which has an electric motor for providing rotation of the antenna and which may be remotely controlled.

Another object of the invention is to provide tate an antenna substantially 360 degrees and which has a stop mechanism at each limit of rotational movement.

Another object of the invention is to provide an antenna rotating mechanism wherein stop means are provided to limit the rotational movement of the antenna and such stop means includes lost motion means so that at least 360 degrees rotational movement may be achieved.

Another object of the invention is to provide a remotely controlled device for rotating an antenna wherein an indicator is provided to indicate the limits of rotational movement of the antenna.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims, taken in 'conjunction with the accompanying drawings, in which:

Figure 1 is a top or plan view of the antenna rotating device;

Figure 2 is a cross sectional elevational view taken along the line 22 of Figure 1;

Figure 3 is a cross sectional plan view taken along the line 33 of Figure 2;

Figure 4 is a cross sectional elevation taken along the line 44 of Figure 3;

Figure 5 is a cross sectional plan view taken along the line 5-5 of Figure 2;

Figure 6 is a perspective view of the antenna rotating device attached to a house and carrying an antenna for rotation, and showing the cables connecting the rotator and antenna to the remote control box and television receiver; and Figure '7 is a schematic diagram of the electrical wiring circuit.

The Figure 6 shows an application of the entire invention wherein an antenna rotator as-' sembly 69 is mounted on the roof of a house and rotatably carries an antenna lfll. The rotator assembly 69 may be remotely controlled at the location of a television receiver H by a an antenna rotating mechanism which will ro- 515 remote control box 10 which is electrically interconnected with the rotator assembly '59 by the remote control cable 8|.

The Figures 1 through 5 may be referred to in order to better understand the construction of the antenna. rotator 89. In the drawings, the reference characters II and I2 designate first and second complementary housing shells which are adapted to be placed together to form a complete housing l3. The first and second housing shells H and H are adapted to be fastened together by bolts 52 which slide within the bores 53 in the housing shell H and threadedly engage the threaded holes 54 in the second housing shell I2. The housing 13 has a top wall portion I4 and a bottom wall portion ii for carrying first and second bearings l6 and I1, respectively. A hollow shaft I3 is adapted to be carried by the housing l3 and has first and second bearing portions l9 and journalling with the first and second bearings l8 and [1; respectively. Thus, the hollow shaft 18 may rotate within the housing I3 and relatively thereto. The housing [3 has an end wall 2| for mounting an electric motor 22. A ring gear 23 is fixedly attached ex terior of the hollow shaft l8 and within the housing l3 for rotation therewith. A power transmission mechanism interconnects the electric motor 22 and the ring gear 23, and such power transmission mechanism is preferably unidirectional so that the antenna will be locked in a given position when the motor 22 is not rotating. Thus the force of the wind or other external forces will not cause rotation of the antenna. Such unidirectional power transmission mechanism has been shown as a gear reduction system 24 and a worm 25 for meshing with the ring gear 23. A terminal wall portion 26 is provided in the lower portion of the housing l3 to provide a terminal box 21 wherein external wiring may be terminated to provide the electric connections to the motor 22.

Stop means 49 are provided for limiting the rotational movement of the hollow shaft l8 relative to the housing 13 and such stop means 49 have been shown in this preferred embodiment as including an abutment or first lug 28 fixedly attached to the hollow shaft l8. The first and second housing shells II and I2 have first and second slot portions 29 and 30, respectively, to provide a continuous slot 3|. A stop slide 32 is adapted to slidably engage the continuous slot 3| and has a second lug or abutment 33. The second lug 33 is adapted to cooperate with the first lug 28 as best shown in Figure 5. The length of the continuous slot 3! is preferably made of a dimension that exceeds the sum of the widths of the first and second lugs 28 and 33 so that the hollow shaft I8 may have slightly greater than 360 degrees rotational movement. The continuous slot 3| and stop slide 32 are preferably T.- shaped in cross section to provide interlocking engagement therebetween, and thus the stop slide 32 can move only longitudinally, and will not become disengaged from this continuous slot'despite any position of the rotator assembly 69. By providing the first and second slot portions 29 and 30 in the two housing shells, the stop slide 32 may easily be inserted in one thereof before assembly, and thence the stop slide 32 will be contained within the continuous slot 3| upon assembly of the two housing shells H and I2. The stop slide 32 sliding within the continuous slot 3| is a lost motion connection between the first lug 28 and the housing 13 and, hence, rotational movement of the hollow shaft I8 is not limited to 360 degrees minus the combined arcuate dimensions, relative to the hollow shaft l8, of the lugs 28 and 33, were the lug 33 to be fixedly attached to the housing 13.

In the preferred embodiment, the lost motion means permits approximately 370 degrees rotational movement of the hollow shaft l8. As shown in Figure 6, the antenna shaft 34 is adapted to be inserted within the hollow shaft IS. The

Figures 1 and 4, the first and second ends 35 and 38 of the hollow shaft [8 have a slot 39 to receive a portion of the U-bolt clamps 31 and 38. Thus, the U-bolt clamps 31 and 38 may b tightened by means of the nuts 40 to fasten the antenna shaft 34 fixedly to the hollow shaft 18. By so providing the slot 39, an antenna shaft 34 which is considerably smaller than the bore of the hollow shaft l8 may still be accommodated and clamped within this hollow shaft. If the antenna shaft 34 is larger in exterior diameter than the bore of the hollow shaft 8, a reducing shaft may be provided and fixedly attached to the antenna shaft 34 to be received within the hollow shaft IS.

The housing l3 has a second end wall to which studs 56 are fixedly attached. Clamp bars 51 are receivable on the studs 55 so that the housing l3 may be clamped to a support shaft 58 as shown in Figure 6. The studs 56 and clamp bars 5'! need not be utilized to fasten the housing l3 to a support shaft but may be used to efiect an attachment of the housing l 3 to any fixed support in any suitable manner.

A signal switch M is provided within the housing l3 and is adapted to be actuated at or near the limit of rotational movement of the hollow shaft l8. The signal switch in this preferred embodiment is simply and ruggedly constructed and includes first and second L-shaped switch blades 42 and 63. The switch blades 62 and 33 have terminal portions Q6 and for attaching to the terminal wall portion 26 of the housing 13. This terminal wall portion 23 is preferably an insulator so that the switch blades 42 and 43 need not be insulated therefrom. The switch blades 42 and 83 also have first and second contact portions 46 and ill which are adapted to mutually contact each other. The hollow shaft l8 has a third lug 48 which is adapted to actuate one or the other of the contact portions 16 and 41 to provide electrical contact between the contact portions 46 and 67. As best seen in Figure 5, the third lug is positioned upon the hollow shaft I8 so that electrical contact will be made between the contact portions #23 and ti, preferably just prior to the limit of the rotational movement of the hollow shaft 83 by the stop means .13. In the preferred embodiment of the invention, such electrical contacting of the blades 16 and at is provided between one and three degrees prior to such limit of rotational movement. Terminals 53 and iii are connected to the terminal portions 6% and 55 within the terminal box 2? so that electrical connection can be made to this signal switch M.

A waterproof rubber shield 53 is preferably provided above the upper bearing 55 to aid in providing a waterproof housing and this waterproof rubber shield 59 has been shown as being dlsposed between first and second collars 3B and 6f, respectively, for supporting and positioning such shield. Preferably the first and second housing hollow shaft l8 has first and second ends 35 and shells H and i2 have the edges 62 and 53, respectively, which are in mutual contact, in a shiplap construction which aids in providing a; waterproof structure. Further, during assembly the edges 62 and 63 may be coated with a liquid waterproof agent to seal the juncture of these two housing shells. A cover plate 66 covers the terminal box 2i to enclose this terminal box. A rubber grommet 65 is provided in an aperture 66 in the bottom wall portion 55 to provide cable access to the terminal box 2?. A cable clamp 6'! may be provided to physically support a cable which contains the wires making electrical connection within the terminal box 21.

A cap I85 is preferably provided at the top of the second end wall 58 and has fins I88 for mechanical strength so that this cap I85 may cover the top of the support shaft 58 to keep out rain and also to act as a supportto prevent the antenna rotator assembly 88 from sliding down the support shaft 58.

The Figure 6 shows the completed antenna rotator mounted upon a support shaft 58 which in turn is attached in any suitable fashion to a fixed support; in this example, the edge of a roof of a house. It is to be understood that the support shaft 58 may be made of any desirable length in order to place an antenna I8I at the desired height. Also, the antenna shaft 88 may be made of any suitable length, although preferably it is kept short and the antenna rotator assembly is thus placed close to the antenna. The housing I8 is preferably made of aluminum or other lightweight metal, so that the weight of the rotator assembly is kept small, thus reducing the tendency to whip upon the support shaft 58. If the support shaft 58 is made quite long, guy wires may be attached to the rotator assembly and pierced cars 88 have been provided for attaching such any wires.

By spacing the bearings I8 and and bottom walls of the housing I8, and by placing the clamp means 81 and 88 outboard of these hearings, the complete antenna rotator assembly 88 has considerable strength in comparison to its small size and light weight.

The Figure 7 shows the schematic electrical wiring diagram for providing remote control of the motor 22. In this Figure 7, the reference character 88 indicates the antenna rotator assembly and the reference character 18 indicates the remote control box. The remote control box 18 is also shown in the Figure 6 and is adapted I1 in the toll to be placed near the radio device for which the antenna is being used. In the Figure 6, the antenna has been shown as being used with a television receiver 1| with the remote control box 18 placed thereon for the convenience of the operator of the receiver H. In Figure '1, the wiring diagram shows that the remote control box 18 includes a transformer 12 having a primary 18 and a secondary 18. A primary switch 15 is adapted to control the energization of the primary '18 from an alternating current source 18. The remote control box has first, se"ond, third and fourth terminals 11, 18, 18 and 88 which are adapted to be connected by a remote control cable 8I to corresponding terminals 82, 83, 88 and 85, respectively, in the terminal box 21 of the antenna rotator assembly 88. A secondary switch 88 is adapted to connect one end 81 of the sec ondary 18 to either the first or second terminals 11 or 18. This secondary switch 88 is a single pole, double throw switch having first and second contacts 88 and 88 connected to the first and second terminals 11 and 18, respectively. The second end 88 of the secondary 18 is connected to the third terminal 18 by conductor 8|. An intermediate tap 82 of the secondary 18 is connected by a conductor 88 and an indicating lamp 88 to thefourth terminal 88. The primary and secondary switches 15 and 88 are preferably adapted to be actuated together as shown by the connecting link 85. A condenser 88 is connected across the first and second terminals 11 and 18.

In the antenna rotator assembly 88, the electric motor 22 is shown as being an induction motor having first and second windings 88 and 81. One end of each of the windings 88 and 81 is connected together at the juncture 88 and the other ends of the first and second windings are connected to the first and second terminals 82 and 88, respectively. The juncture 88 is connected to the third terminal 88 and is connected through the signal switch H to the fourth terminal 85. The condenser 88 has been shown within the remote control box 18 to shift the phase of one of the windings 88 and 81 relative to the other in order to provide starting torque and rotation of the electric motor 22 in a governable direction.

The remote control cable 8| has been shown in the Figure 6 and interconnects the remote control box 18 and the rotator assembly 88 at the terminal box 21. Further, in Figure 6 an antenna lead-in I88 has been shown interconnecting the antenna IN and the television receiver H. The remote control box I8 has been shown as deriving electrical energy from the alternating current source 18 by a power cord I82 and a wall outlet I88. A power cord I88 is also shown as being connected to the wall outlet I83 and supplies energy to the television receiver H. The Figure 6 shows the remote control box 18 as having a switch knob I81 for actuating the primary and secondary switches 15 and 88, which switch knob has a neutral position and may be actuated either to the right or left to cause the switch 88 to contact either the contact 88 or 88. Further, the remote control box 18 may have a translucent panel I 88 behind which the indicating lamp 88 may be mounted. The translucent may be provided with any suitable legend, and

in the preferred embodiment, the translucent panel has been provided with a legend reading, "End of rotation, reverse switch."

Operation As previously stated, the primary and secondary switches 15 and 88 are interconnected for actuation and the secondary switch 88 is adapted to be closed before the closing of the contacts of the primary switch 15. This permits lighter duty contacts at the secondary switch 88 since it does not interrupt the heavier secondary current, and further the primary switch 15 being normally open, permits the use of an intermittent duty transformer 12. When the secondary switch 88 is thrown to contact either the first or second contacts 88 and 88 the primary switch 15 is thereupon closed to energize the transformer 12.

. If the secondary switch 88 makes contact through the first contact 88, then the first motor winding 88 will be directly energized and the second motor winding 81 will be energized through the condenser 88 to start the motor 22 rotating in a given direction. If the secondary switch 88 makes contact through the second contact 88, then the second motor winding 81 is energized directly and the first motor winding 88 is energized through the condenser 88 to provide rotation of the motor 22 in the opposite direction. The motor energization circuit is completed through the third terminals 88 and 18 to the second end 88 of the secondary 18. As previously explained, the indicating switch H is actuated by the third lug 88 on the hollow shaft I8 and is adapted to be actuated approximate y one to three degrees prior to the limit of rotational movement bv the stop means 88. When the signal switch 8| is actuated to an electrically closed condition, a circuit is completed through the lower half of the secondary 18, through the third terminals 18 and 88,

the signal switch, and the indicating lamp 94 to return to the intermediate tap 92 of the secondary 14. This closed circuit will thus energize the indicating lamp 94 and thus give an indication that limit of rotation of the antenna llll has been reached.

Thus, the invention provides an antenna rotator assembly which provides for quick and accurate orientation of an antenna for facilitating the improved reception of a desired signal. The use of the gear reduction system 24 provides a relatively slow rotation of the antenna IM and by using the worm 25, the antenna is self-locking in that wind or other external forces will not be able to rotate the antenna. The housing shells I I and 12 are preferably made of aluminum "castings which provide considerable strength to the rotator assembly and yet provide a light and small structure which does not cause undue strains upon the-supporting shaft 58. By providing approximately 370 degrees rotation, the antenna may be oriented to best receive the desired signal. Further, since any antenna is slightly directional and especially those antenna arrays designed to be primarily unidirectional may be oriented to obtain the greatest ratio of desired signal to interference. A directional antenna -will have a major lobe and smaller spurious lobes as shown on a horizontal radiation pattern and between such lobes there will -be nulls. By so directing a null toward an interfering station, the maximum ratio of desired signal to interference may be obtained.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangements of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

l. A device for providing relative rotational movement between a shaft and a housing, comprising ahollow shaft extending longitudinally through and journalled in said housing to receive said shaft, clamp means near the longitudinal extremities of said hollow shaft adapted to fixedly attach said hollow shaft to said shaft receivable therein, an electric motor and a power train within said housing and interconnecting said housing and said hollow shaft for relative rotation, and means to provide electrical connection to said electric motor.

2. A device for providing relative rotational movement between two shafts, comprising a housing, a hollow shaft extending longitudinally through and journalled in saidhousing to receive one of said two shafts, clamp means near the longitudinal extremities of said hollow shaft adapted to fixedly attach said hollow shaft to said shaft receivable therein, an electric motor.

and a power train within said housing and interconnecting said housing and said hollow shaft for relative rotation, means for fixedly attaching said housing to the other of said two shafts, and

ing longitudinally through and journalled in said f housing to receive said shaft of said device, clamp means near the longitudinal extremities connecting said hollow shaft and said electric motor, electrical connection means for said electric motor, and stop means for limiting relative rotational movement between said hollow shaft and said housing, said stop means including an abutment adapted to rotate in accordance with said relative rotation, a second abutment carried by said housing and adapted to cooperate with said first' abutment, one of said abutments having a lost motion connection with the element carrying same, such that said relative rotational movement at least equals.360 degrees.

4. A device for rotating an antenna having a shaft, comprising, a weatherproof housing, a hollow shaft extending longitudinally through and weatherproofiy join'na'lled in said housing to receive said antenna shaft, clamp means near the longitudinal extremities of said housing adapted to fixedly clamp said antenna shaft to said hollow shaft for rotation therewith, an electric motor mountedv in said housing, power train means for interconnecting said hollow shaft and said electric motor, stop means for limiting rotational movement of said hollow shaft, said stop means including a first lug axially projecting from said hollow shaft, a second lug carried by said housing, and lost motion means including said second lug and disposed between said first lug and said housing.

5. A device for rotating an antenna having'a shaft comprising, a weatherproof housing having an end wall, a hollow shaft extending vertically through and journalled in said housing to receive said antenna shaft, a ring gear fixedly attached-to and externallyof said hollow shaft within said housing, clamp means above and below said housing adapted to fixedly clamp said antenna shaft to said hollow shaft for rotation therewith, an electric motor mounted to said end wall within said housing, gear reduction means including a worm gear meshing with said ring gear for rotating said hollow shaft from said electric motor, stop means for limiting rotational movement of said hollow shaft, said stop means including a first lug axially projecting from said hollow shaft, a second lug carried by said housing, lost motion means including said second lug and disposed between said first lug and said housing, and signal switch actuating means including a third lug radially projecting from said hollow shaft, two substantially parallel spaced spring contact members carried by said housing and adapted to be contacted by said third lug, one of said spring contact members adapted to be contacted by said third lug and urged into contact with the other of said spring contact members near each limit of rotation of said hollow shaft approximately 1 degree to 3 degrees prior to the limit of rotation of said hollow shaft .by said stop means.

6. An antenna rotator for an antenna having a shaft, comprising, first and second complementary housing shells interfitting to form a weatherproof housing, means on said housing to fasten said housing to a fixed support, first and second longitudinally opposite end walls in said housing, bearings carried by said end walls, a hollow shaft weatherproofiy journalled in said bearings and having first and second ends extending beyond said first and second end walls, respectively,

' a clamp carried external of said housing by each of said first and second ends to clamp the shaft of said antenna receivable in said hollow shaft, an electric motor fastened within said housing, a ring gear fixedly attached to said hollow shaft within said housing, unidirectional gear train means including a worm gear meshing with said ring gear for driving said hollow shaft from said electric motor, and terminal connection means for providing electrical connection to said electric motor.

'7, An antenna rotator for an antenna having a shaft, comprising, first and second complementary housing shells interfitting to form a weatherproof housing, means on said housing to fasten said housing to a fixed support, first and second longitudinally opposite end walls in said housing, bearings carried by said end walls. a hollow shaft weatherproofiy journalled in said bearings and having first and second ends extending beyond said first and second end walls, respectively.

a clamp carried by each of said first and second ends external of said housing to clamp the shaft of said antenna receivab'e in said hollow shaft. an electric motor fastened within said housing, a ring gear fixedly attached to said hollow shaft within said housing, unidirectional gear train means including a worm gear meshing with said ring gear for driving said hollow shaft from said electric motor, terminal connection means for providing electrical connection to said electric motor, and stop means for limiting rotational movement of said hollow shaft, said stop means including a first lug radially projecting from said hollow shaft, a slot in each of said housing shells adapted to form one continuous slot, a stop slide engaging and sliding within said continuous slot and having a given longitudinal length, said first lug having a first given width, a second lug on stad stop slide adapted to engage said first lug upon rotational movement of said hollow shaft, said second lug having a second given width, the length of said continuous slot exceeding the length of said stop slide by an amount at least equal to the sum of said given widths to thereby permit at least 360 degrees rotational movement of said hollow shaft.

8. An antenna rotator for an antenna having a shaft, comprising, first and second complementary housing shells interfitting to form a weatherproof housing, means on said housing to fasten said housing to a fixed support, first and second longitudinally opposite end walls in said housing, bearings carried by said end walls, a hollow shaft weatherproofiy journalled in said bearings and having first and second ends extending beyond said first and second end walls, respectively, a clamp carried by each of said first and second ends to clamp the shaft of said antenna receivable in said hollow shaft, an electric motor fastened within said housing, a ring gear fixedly attached to said hollow shaft within said housing, unidirectional gear train means including a worm gear meshing with said ring gear for driving said hollow shaft from said electric motor, terminal connection means for providing electrical connection to said electric motor, and stop means for limiting rotational movement of said hollow shaft, said stop means including a first lug axially projecting from said hollow shaft, a slot in each of said housing shells adapted to form one continuous slot, a stop slide engaging said continuous slot, said first lug having a first width establishing a first arcuate dimension relative to said hollow shaft, a second lug on said stop slide adapted to engage said first lug upon rotational movement of said hollow shaft, said second lug having a second width establishing a second arcuate dimension relative to said hollow shaft, a given angle being established by 360 degrees less the sum of said first and second arcuate dimensions, said stop slide having a lost motion connection with said continuous slot such that the rotationa1 movement of said hollow shaft exceeds said given angle.

9. A device for rotating an antenna shaft relative to a fixed support, comprising a first member adapted to be fixedly attached to said fixed sup .port, a second member revoluble relative to said first member, an electric motor and a power train interconnecting said first and second members. electrical means carried by one of said members, said electrical means having two electrical connections and operable to produce a changed electrical condition across said two electrical connections, second means carried by the other of said members for operating said electrical means, terminals adapted to be connected to a source of electrical power, and an indicator connected in circuit with said terminals and the two electrical connections of said electrical means for indicating at least one rotational position of said second member.

10. A device for rotating an antenna shaft relative to a fixed support, comprising a first member adapted to.be fixedly attached to said fixed support, a second member revolube relative to said first member, an electric motor and a gear train interconnecting said first and second members, first and second abutment means on said first and second members respectively, lost motion means disposed between said abutment means, stop means including said abutment means and said lost motion means to limit the rotation of said second member to approximately 360 degrees, indicator switch means including at least one of said abutment means and said lost motion means and actuable at least at said rotational limits, terminals adapted to be connected to a source of electrical power, and an electrically operated indicator connected in loop circuit with said terminals and said indicator switch means to indicate at least said rotational limits.

11. A device for rotatingan antenna shaft relative to a fixed support, comprising a first member adapted to be fixedly attached to said fixed support, a second member revoluble relative to said first member, an electric motor and a gear train interconnecting said first and second members, an abutment on said second member, switch means fixed relative to said first member and actuable by said abutment from either of the two rotational directions, the combination of said abutment and said switch means having a lost motion connection to establish actuation of said switch means substantially at either end of 360 degree rotational movement of said second member, terminals adapted to be connected to a source of electrical power, and an indicator connected in loop circuit with said terminals and said switch means to indicate the limits of rotational movements of said second member.

12. A device for rotating an antenna having a shaft comprising, a weatherproof housing having an end wall, a hollow shaft extending vertically through and journalled in said housing to receive said antenna shaft, a ring gear fixedly attached to and externally of said hollow shaft within said housing, clamp means above and below said housing adapted to fixedly clamp said antenna shaft to said therewith, a reversible electric motor mounted hollow shaft for rotation to said end wall within said housing, gear reduction means, including a worm gear meshing with said ring gear for rotating said hollow shaft from said electric motor, a transformer adapted to be energized from an alternating current source, primary switch means for controlling the energization .of the transformer primary from said alternating current source, secondary reversing switch means controlling the energization of said motor from said transformer secondary for forward and reverse rotational movements, signal switch means in said housing, actuating means on said hollow shaft for actuating said signal switch means at either end of substantially 360 degree rotational movement of said hollow shaft, stop means for limiting rotational movement of said hollow shaft to approximately 360 degrees, a signal light for indicating either end of substantially 360 degree rotational movement of said antenna shaft, and connection means including at least a part of said transformer secondary for energizing said signal light upon closing of said signal switch means.

13. A device for rotating relative to a fixed support an antenna having a shaft comprising, a weatherproof housing having an end wall, a hollow shaft extending vertically through and journaled in said housing to receive one of said antenna shaft and said fixed support, means for fixedly attaching said housing to the other one of' said antenna shaft and said fixed support, clamp means above and below said housing adapted to fixedly clamp said one'of said an tenna shaft and said fixed support to said hollow. shaft for rotation therewith, a ring gear fixedly attached to and externally of said hollow shaft within said housing, an electric motor mounted to said end wall within said housin gear reduction means including a worm gear' meshing with said ring gear for rotating said hollow shaft from said electric motor, signal switch means in said housing, and actuating means on said hollow shaft for actuating said signal switch means at either end of substantially 360 degree rotational movement of said hollow shaft.

14. A device for rotating an antenna shaft relative to a fixed support, comprising a first member, a second member revoluble relative to said first member, one of said members being hollow to receive one of said antenna shaft and said fixed support, an electric motor and a power train interconnecting said first and second members, electrical means carried by one of said members, said electrical means having two electrical connections and operable to produce a changed electrical condition across said two electrical connections, second means carried by the other of said members for operating said electrical means, terminals adapted to be connected to a source of electrical power, and an indicator connected in circuit with said terminals and the two electrical connections of said electrical means for indicating at least one rotational position of said second member.

15. A device for rotating an antenna shaft relative to a fixed support, comprising, a first member adapted to be fixedly attached to said fixed support, a second member revoluble relative to said first member to rotate said antenna shaft,

an electric motor and a power train interconnecting said first and second'members to rotate said second member, electrical means carried by said first member, said electrical means having two electrical connections and operable to produce a changed electrical condition across said two electrical connections, second means driven from said power train for operating said electrical means, terminals adapted to be connected to a source of electrical power, and a position indicator controlled by a circuit including said terminals and the two electrical connections of said electrical means.

16. A devicefor rotating an antenna shaft relative to a fixed support, comprising a first member adapted to be fixedly attached to said fixed support, a second member revoluble relative to said first member, an electric motor and a power train interconnecting said first and second members, electrical means carried by one of said members, second means carried by the other of said members for operating said electrical means, the combination of said electrical means and said second means having two electrical connections and operable to produce a changed electrical condition across said two electrical connections, terminals adapted to be connected to a source of electrical power, and an indicator connected in circuit with said terminals and the said two electrical connections for indicating at least one rotational position of said second member.

17. A device for rotating an antenna shaft relative to a fixed support, comprising, a first member adapted to be fixedly attached to said fixed support, a second member revoluble relative to said first member to rotate said antenna shaft, an electric motor and a power train interconnecting said first and second members to rotate said second member, electrical means carried by said first member, second means driven from said power train for operating said electrical means, the combinationof said electrical means and said second means having two electrical connections and operable to produce a changed electrical condition across said two electrical connections, terminals adaptedto be connected to a source of electrical power, and a position indicator controlled by a circuit including said terminals and the said two electrical connections.

RICHARD H. JORDAN.

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